When you configure the Portal Server 7 gateway, the configurator tries to record configuration information into the LDAP server on the intranet. For this purpose, the Cacao server on the intranet connects to the Cacao server running on the Portal Server node, which copies data to the LDAP server. For this data transfer to happen, an explicit trust must be established between the Cacao servers on the intranet gateway node and the Portal Server node. Trust can be established by copying the security folder from the Cacao install on the portal node to the security folder on the Cacao install on the gateway node.
The manual step to establish trust between two nodes is automated in the Sun Java System 5 Portal Server SRA 7.1 release.